Concentric polymer-dispersed liquid crystal rings for light intensity modulation

This paper presents a tunable artificial iris on flexible substrate for modulating light intensity through human eyes. The artificial iris consisted of eight rings of polymer-dispersed liquid crystals (PDLCs). These PDLC rings were switched between transparent and opaque states by applying a 100 V bias voltage. A control circuit with a photodiode was integrated to sequentially drive the PDLD rings in response to the ambient light. The transmittance of the fabricated artificial iris was decreased from 94% to 20.4% as the ambient light intensity increased from 0 lux to 2500 lux. When the ambient light intensity was 2500 lux, the modulated value passing through the artificial iris was reduced to 510 lux. The presented system can be potentially applied for assisting patients of aniridia or enhancing the functionality of robot vision.